Air preheater



M. M.' YALE AIR PREHEATER Sept. 30, 1930.

Filed D80. 1927 N/L'roN l'l. Yms.

- INVENTOR.

HTTORNEx away.

' wardly to the outer walls 31, then along these see ed Sept. 30,1930

were stars rATENT OFFICE;

MILTON ivr. YALE, or Mommas, QUEBEC, CANADA AIR PREHEATER' Application filed December This invention relates to means for promoting combustion 1n furnaces and the like and particularly to meanswhereby the air" is preheated before it reaches the combos tion area.

Its object is to promote more complete combustion of the fuel gases and eli ninate smoke and thereby obtain the maximum heating effect from the fuel consumed in the furnace.

A further object is to provide a simple,

compact and eflicientair preheater which can be readily applied to furnaces without alter a-tion and without the aid of skilled labour.

In the description of my invention reference will be made to the accompanying drawings in which y V Fig. 1' is a perspective view, partly cut central horizontal cross section. vertical cross section on the line 2 Fig. a

F1 3 is a 3-43 of Fig.

4 is a view of the removable cover.

7 The furnace door l, with its air inlet 10, is fitted with a two part device comprising an outer part 2, providing an air chamber 20, with a central air inlet 21., and side in ct.

anl an inner part consisting of a box slurp-co m. 3, with a series of vertical therein. These partitions 80,

partitions 30, form the walls of vertical heat passages 4-. and t0, and of horizontal air passages 5.

The heat passages include the large U- shaped passage 4, and two small passages -lO, parallel to the central vertical partition 32. I The partitioi'is forming the walls of these "ages so situated that the air passages cine narrower from the inlet'to the outlet; T he air passages 5, are two innumber, dividingat the aperture 36,'and flowing out removable, permitting the air passages to be readily cleaned without delay. Thev front wall of the casing has a central aperture 36,

and extends outwardly to form a flange 37, r

5, 192?. Serial no. 237,810.

to which the outer part 2 holes bored in the furnace door 1,,

lVhenth'is device is mountedon a'furnace door and the door is closed,the casing projects into the furnace over the fuel bed, and is exposed to the radiated heat of the burn in fuel and to the heat of the gases rising from the fuel bed, some of which pass up wards through the heat passages and thereby heat the walls, the bottom and the top of the casing.

The air entering the inlet is first warmed in the outer chamber and then passes through theapertures to the casing into the passages which are surrounded by heated walls. As it flows onwardand absorbs the heat of the surrounding metal surfaces it expands, but owing to the right angle turns of the passages which act as baffles, its speed rapidly increases until it reaches the nozzle and its slit outlet through which it flows as arapid blast in a fan shaped path over the fuel bed. v

This blast of highly heated air spreads and mixes with the fuel gases rising from the fuel bed and produces a highly efficient combustion.

What I claim is 1. In an air preheater, afurnace having a door with an air inlet therein, a casing attac-hed to the inside of the door .and communicating-with said inlet, air passages in the ca'sing leading from the inlet anddoubling inwardly on themselves to a central nozzle outlet in the end of the casing, with vertical passages for the passage of combustion gases, through the casing, formed by the walls of the air passages. V I

2. In an air preheater, a furnace having adoor with an air inlet therein. a casing at tached to the inside of the door, and com- .inunicating with said inlet, air passages in is bolted through the casing leading from the inlet and donbling inwardly on themselves, diminishing incross' section, to a central nozzle outlet 3.111 an air preheater, a furnace having a door with an air inlet therein, a casing attached to the lnsnle of the door and comnimncuting with said inlet, vertical partillOllS H) the casin to form horizontal air passages leading iroln the inlet and doubling inwardly on themselves to a central nozzle outlet in the end of the casing, with vertloal passages for the'paeszwe 0t oonihustiongzises, 4. .1 l V '1 ,4. imongni the casing, ioinied by tne vertical partitions.

T. in an air preheater, a furnace having a door with an air inlet therein, a casing attached 10 the inside of the door LUMl'COIIP municnting' with said inlet, vertical perti tions in the casing to form horizontal air we leading; from the inlet and clouhling: inwardly on themselves to a central nozzle outlet in the enkl of the casing, with vertical passages for the passage of comhus tion gaseza, through the casing between the bends m. the horizontal passages, formed by the vertical partitions.

MILTON M. YALE 

